Motor-control system.



H. W. CHENEY. MOTOR CONTROL SYSTEM.

I 7 APPLICATION FILED APR. 15, 1910. 992,852.

Patented May 23, 1911.

2 BHEETS-SHBET 1.

H. W. CHENEY.

MOTOR CONTROL SYSTEM. APPLICATION 211.31) APB..15, 1910 992,852.Patented May 23,1911. Q

2 SHEETS-SHEET 2.

I. m: "h. IIII III-110mm UNITED STATES PATENT OFFICE.

HERBERT W. CHENEY, OF MILWAUKEE, WISCONSIN, ASSIGNOR T0 ALLIS-CHAIMERSCOMPANY, A CORPORATION OF NEW- JERSEY.

moron oon'rnor. SYSTEM.

Specification of Letters ZPatent. P t nted May 23, 1911.

Application filed April 15, 1910. Serial No. 555,624.

Liquid rheostats when used for controlling motors of large size requireconsiderable power for their operation. I therefore propose to provide acontrol system in which there is a remotely controlled power-operatedliquid rheostat, there being a number of novel features in the systemitself as well as in the rheostat proper and its operating means. Byreason of these new features, the operator controlling the s stem hashis physical labor materially lig tened, the system is protected againstaccident due to unskilfulness on the part of the operator, and the sizeof the liquid rheost-at proper is much reduced. Moreover, in case thesystem is a polyphase system, the structure of the rheostat provides forpreventing or counteracting any tendency toward unbalancing.

The various novel features of my invention will be apparent from thedescription and drawings, and will be particularly pointed out in theclaims.

Figure 1 is a diagrammatic view showing a system embodying my invention;Fig. 2 is .a plan View of a liquid rheostat constructed in accordancewith my invention; Fig. 3 is a section-on the line 33 of Fig. 2; Fig. 4is a detail view taken substantially on the line 44 of Fig. 2; and, Fig.5 is an elevation of part of the-reversing switch and its operatingmechanism.

The motor 8 is the motor to be controlled. It may be used for anydesired purpose, be ing illustrated as operating thev winding drum 9 ofthe hoist or elevator 10. It is here shown as a three phase motor havingits primary supplied from a suitable source of alternating currentthrough the circuitbreaker 11 and the reversing switch 12, and its woundsecondary connected to the plates of a liquid rheostat 13. Theresistance of the rheostat is varied by adjusting the level of theliquid therein by varying the height of one or more overflow pipes orweirs 14,

the liquid overflowing into a tank 15; from which it is pumped, as by amotor-driven centrifugal pump 16, into the rheostat 13. This continuouscirculation of the liquid, which is preferably acidulated water, re-

duces the temperature of the rheostat and enables a much smallerrheostat to be used for the work than could otherwise be used. The weirs14 and the reversing switch 12 are operated'by an air en ine 17, airunder pressure being supplied rom any suitable source 18. The air engineis provided with i an oil lock 19, which prevents its accidentalmovement. If desired, the oil lock may be omitted, or a suitable dashpotor.cataract may be substituted for it. The direction and extent of themovement of the air engine and the relation .between the direction ofits movement and that of the movement of the reversing switch arecontrolled by the master control lever 20.

The rheostat 13 has a casing 21, which is preferably rovided with fourinteriorly projecting a utments 22, 23, 24, and 25. This casing may bemade of any desired material, concrete being especially suitable. Wateris supplied to the casing through the inlet pipe 26, which extends fromthe pum 16, enters the rheostat near the top, an passes downward-almostto the bottom between the abutments 23 and 24. By this means muchobnoxious splashing is avoided.

In the arrangement shown there are two overflow pipes or weirs 14, thesebeing located respectively between the abutments 22 and 23, and 24 and25. The abutments prevent the passage of the liquid directly from theinlet pipe to the overflow weirs. The weirs 14 are swung by links 27from arms 28 fixed on a shaft 29, the latter-being preferably supportedin bearings 30 on the casing 21. The shaft 29 is rotatable by the airengine 17, through suitable connecting mechanismn The downward movementof the weirs 14 is limited by cooperating shoulders 31 and 31, solocated that the level of the water in the casing 21 is alwayssufficiently high to cover the lower ends of the rheostat plates 32.These rheostat plates 32 are suspended from two bars 33 which extendlengthwise across the casing 21 near its top. The bars 33 are preferablyof wood or other insulating material, though they may be of conductingmaterial if other suitable provision is made for insulating the plates32 to move downward to cut out resistance with the reversing switch 12in the position opposite to the one corresponding to that of the lever20. Movementi'iof such lever beyond the oil position is'thus preventedat this time. The movement of. the lever 20 to off position throws the"valves 43 and 44 to admit air pressure below the piston 39 and toconnect the spaces on the two sides of the piston 40, and also operatesthe cam 48 to throw the levers 49 back to their middle position and putthe right hand spring 66 under compression tending to disengage the riht hand gear 50 firom the gear 51. Such isengagement, however, isprevented at this time by the finger 52 and the plate 54. The airpressure beneath the piston 39 raises such piston and the piston rod 41,and allows the weirs 14 to drop, thus lowering the level of the water inthe rheostat and increasin the resistance of the secondary circuit 0 themotor 8. Downward movement of the weirs 14 continues until the shoulders31 and 31 stop it, whereupon the piston rod 41, continuing its upwardmovement, throws the cam 62 to its central position, thus moving thegear 51 to open the switch 12 and to bring the finger 52 in line withthe slot 53. WVhen. the finger 52 reaches this position, the right-handspring 66.

which is now compressed, throws the righthand bevel gear 50 outofengagement with the cooperating gear 51. When the piston rod 41reaches its upper limit of movement it releases the latch 42 to allowmovement of the master control lever 20, and also, acting throughthe-floating lever v-57 and the links 58 and 59, closes the valves 43and 44 to stop such upward movement. The master control lever 20 maynow' be moved to the right to cause the reversal of the motor 8. Forsuch movement to the right the operation is the same-as that describedabove for movement to the left, save that the cam 48 is moved in aclockwise direction from its central position to cause the left handbe'vel gear 50 to cotiperate with the gear 51 and to close the reversingswitch 12 to the. right, and the finger 52 to'be moved tothe right handside of the plate 54.

Should the voltage on the supply mains fail at any time, the no-voltagerelease coil 67 allows its core to drop to release the circuit-breaker11, the latter then opening auto matically. If the motor is running atthis time, it. will be brought quickly to astandstill by the operationof the electro-mechanical brake 68, the. releasing coil of which isenergized only when the circuit-breaker 11 is closed. This brake canalso be appliedat any time, if desired, by opening the switch 69. Thismay be desirablein sto ping the motor 8. If esired, a niechanicall y ormanually operated brake may be used instead or in addition. In case theoperator should a1 tained energized until the motor 8 has been operatedfar enough in the reverse direction to cause the car 10 to allow theswitch 70 to close. An emergency switch 72 may also be provided in thecircuit of the no-voltage coil 67, for causing the deenergization ofsaid coil and the consequent opening of the circuit-breaker 11 andapplication of the brake 68 should such be desired. In case of anoverload on the motor8 the overload coil 73 lifts the latch 74 of. thecircuit-breaker 11 and releases it from the core of the no-voltage coil67, thus allowing the circuit-breaker 11 to open and causing theimmediate application of the brake 68. The no-voltage coil 67 and therelease coil of the brake 68 are preferably supplied through a potentialtransformer or o transformers 75, and the switches 69, 71, and 72 arepreferably located conveniently for the operator. These switches may beof the push-button type, the switches69 and 72 tion I aim to cover inthe following claims.

What I claim as new is:

1. In combination, a casing for a liquid rh'eostat, electrodes locatedin said casing, means for pumping a liquid from a source of supply intosaid casing, and a vertically adjustable overflow weir associated withthe casing for determining the height to which the liquid rises in thelatter.

2. A liquid rheostat including a casing containing liquid and electrodeswithin said casing, in combination with a unitary poweroperated devicefor gradually varying the height of the electrodes in relation to thelevel of the liquid in the casing.

3. In combination, rheostat, electrodes in supplying liquid to saidcasing, a discharge conduit for allowing the liquid to flow out of thecasing, and unitary means for gratin-- ally varying the height of theentrance to said discharge conduit.

4. A liquid rheostat including a' casing a casing for a liquid; saldcasing, means for and electrodes within the casing, in combina- I foradjusting said overflowpipe vertically.

prising 5. A liquid rheostat including a casing and electrodes withinthe casing, in combination with means for supplying liquid to said casinan overflow pipe vertically adfor controlling the operation of saidfluid engine both manually and by the movement produced by the engine.

i. In combination, a liquid rheostat coma casing and electrodes within.the casing, a fluid engine for varying the height of the electrodes inrelation to the level of the liquid within said rheostat, and means forcontrolling said engine both manually andvby its own movement.

8. In combination, a liquid rheostat comprising a casing and electrodeswithin the casing, a fluid engine for varying the height of theelectrodes in relation to the level of the liqiliid within saidrheostat, means for contro ing said engine both manually and by its ownmovement, and aliquid lock for preventing movement of said engine unlesssuch movement is produced by the pressure of the fluid supplied to theengine.

9. In combination, a casing for a liquid rheostat, electrodes within thecasing, means for supplying liquid to said casing, an overflow weirassociated with the casing, a fluid enginefor movin said weirvertically, and means for control ing said engine both manually and byits. own movement.

, 10. In combination, a casing for a liquid rheostat, electrodes withinthe casing, means for supplying liquid to said casing, an overflow weirwithin the ca'sing, a fluid engine for moving said weir verticallywithin the casing, means for controlling said engine both manually andby its own movement, and a li uid lock for preventing movement of saiduid engine savewhen motive fluid is supplied to it.

11. In combmat1on, a variable resistance, a. reversing swltch, a fluidenglne, and mechanical connections whereby said fluid engine by movementin a given direction may operate said reversing switch in'eitherdirection and varies said resistance.

12. In combination, a variable resistance, a reversing switch, a fluiden 'ne, mechanical connections whereby said uid engine operates saidreversing switch and varies said resistance, and means for controllingsaid fluid engine both manually and by its own movement.

13. In combination, a variable resistance,

ceases areversing switch, a fluid en 9 1e, mechanical connectionswhereby said uid engine operates said reversing switch and varies saidresistance, and meansior reversing the relation between a given movementoic the fluid engine and the resultant movement of the reversing switch.

1 In combination, a variable resistance,

' a reversing switch, a fluid en. 'ne, mechanical connections wherebysaid uid engine 0p-' crates said reversing switch and varies saidresistance, means for reversin the relation between a given movement 0'the fluid engine and the resultant movement of the reversing switch, andmeans for preventing such reversal save when the reversing switch isopen.

15. In combination, a variable resistance,

a reversing switch, a fluid engine, mechanical connections whereby saidfluid engine operates said reversing switch and varies said resistance,means for reversing the relation between a given movement of the fluiden gine and the resultant movement of the versing switch, and means forcontrolling said fluid engine both manually and by its own movement.

16. In combination, a variable resistance, a reversing switch, a fluidengine, and mechanical connections from said engine to said resistanceand said switch whereby a movement of the engine from one limit oi itsmovement first closes said switch and then reduces such resistance.

'17. In combination, a variable resistance, a reversing switch, a fluidengine, mechanical connections from said engine to said resistance andsaid switch whereby a movement of the engine from one limit of itsmovement first closes said switch and then reduces such resistance, andmeans for controlling said engine. v I

I8.- In combination, a variable resistance, a reversing switch, a fluidengine, mechanical connections from said eng nqto said resistance andsaid switch wherb a movement of the engine from one limit of itsmovement first closes said switch and'then reduces such resistance, andmeans tor re} versing the direction in which such movement of the enginecloses such reversing switch.

19. In combination, a variable resistance, a reversing switch, a fluiden e, mechanical connections from said engine to said resistance andsaid switch whereby a movement of the engine from one limit of itsmovement first closes said switch and then reduces such resistance,means for reversing the direction in which such movement of the enginecloses such reversing switch, and means .for preventing such reversalsave when the reversing switch is in open position.

20. In combination, a variable resistance,

a reversing switch, .a fluid engine, mechanical connections from saidengine to said resistance and said-switch whereby a movement of theengine from one point ofits movement first closes said switch and thenreduces such resistance, and means for controlling said fluid engineboth manually and by its own movement.

. a reversing switch, a fiuid englne, mechanical connections-from saidengine to said resistance and said switch whereby a movement of said enine from one limit of its movement first closes said switch and then 1reduces such resistance, means for controlling said fluid engine bothmanually and by its own movement and for reversing the relation betweenamovement of the fluid engine and the resultant'movement of thereversing switch, and means for preventing such reversal save when saidengine is at its aforesaid limit of movement.

23. In combination, a variable resistance, a reversing switch, a fluidengine, mechanical connections from said engme to said resistance andsaid switch whereby a movement of the engine from one point of itsmovement first closes said switch and then reduces such resistance,means for controlling said fluid engine both manually and by its ownmovement, and means for preventing movement of the manually operatedmeans for controlling the fluid engine from one side of the ofl positionto the other save when the engine is at the aforesaid point.

24. In combination, a fluid engine, a reversing switch, and means formechanically connectin said reversing switch to said fluid englne sothat a given movement of the engine may operate the reversing switchineither direction.

25. In combination, a fluid engine, a reversing switch, means formechanically connecting said reversing switch to said fluid engine sothat a given movement of the engme may operate the reversing switch in,

either direction, and means for preventing the breaking of suchmechanical connect-ion .save when the reversing switch is inopenposition.

26. In combination, a fluid engine, a reversin switch, and meansarranged when moved on either side of a neutral position to control inthe same manner the supply of fluid to said engine and when moved onopposite sides of the neutral position to make mechanical connectionsbetween the engine and the switch so that the same movement of theengine causes opposite movements of the switch.

27. In combination, a fluid engine, a reversing switch, means arrangedwhen moved on either side of a neutral position to control in the samemanner the supply of fluid to said engine and when moved on oppositesides of the neutral position to make mechanical connection between theengine and the switch so that the same movement of the engine causesopposite movements of the switch, and means for preventing saidcontrolling means from moving from one side of neutral position to theother save when the reversing switch is open.

28; In combination, a fluid engine, a re: versing switch, means arrangedwhen moved on either side of a neutral position to control in the samemanner the supply of fluid to the engine and when-moved on oppositesides of the neutral position to make mechanical connections between theengine and the switch so that the same movement of the engine causesopposite movements of the switch, and means for preventing the breakingof such mechanical connections save when the reversing switch is open.

29. In combination, an electric motor, a variable resistance in circuittherewith, a reversing switch in the supply circuit of said motor, andunitary power-operated means arranged when moved in one direction fromone limit of its movement first to close said reversing switch andsecond to reduce the amount of such resistance in circuit with themotor.

30. In combination, an electric motor, a variable resistance in circuittherewith, a reversing switch in the supply circuit of said motor,unitary power-operated means arranged when moved in one direction firstto close said reversing switch and second to reduce the amount of suchresistance in circuit with the motor, and means for reversing thedirection in which the initial movement of such power-operated means insaid direction closes the reversing switch.

31. In combination, a liquid rheostat comprising-a casing and electrodeswithin the casing, power-operated means for varying the height of theelectrodes relatively" to the level of the liquidwithin the rheostat,and means for controlling said power-operated means both manually and bythemovement it produces.

32. In combination, a casing-for a liquid rheostat, electrodes withinthe casing, means .for supplying liquid to said casing, an overflow welrassociatedwith the casing, poweroperated means for moving saldweir ver=tically, andmeans for controlling said power operated means bothmanually and'jby the movement it produces. 33. In combination, avariable resistance, a reversing switch, a power-operated 'device, andmechanical connections between said device, said resistance, and saidswitch whereby said device by movement in a given direction may operatesaid reversing switch in either direction and varies. said resistance.

34:. In combination, a variable resistance, a reversing switch, apower-operated device,, mechanical connections between said device, saidresistance, and said switch whereby said device by movement in a givendirection may operate said reversin switch in either direction andvaries said resistance, and means for controlling said device bothmanually and by its own movement.

85. In combination, a variable resistance, a reversing switch, apower-operated device, mechanical connections whereby said deviceoperates said reversing switch and varies said resistance, and means forreversing the relation between a given movement of said device and theresultant movement of the reversing switch.

36. In combination, a variable resistance, a reversing switch, apower-operated device, mechanical connections whereby said deviceoperates said reversing switch and varies said resistance, means forreversing the relation between ,a given movement of said device andtheresult'ant movement of the reversing switch, and means for preventingsuch reversal save when the reversing switch 1s 0 en.

3% In combination, a variable resistance, a. reversing switch, apower-operated device, mechanical connections whereby said device,operates said reversin switch and varies. said resistance, means Iorreversing the re lation between a given movement of said device and theresultant movement of the reversing switch, and means for controllingsaid device both manually and by its own movement. I

38. In combination, a variable resistance, a reversing switch, apower-operated device, and mechanical connections from said device tosaid resistanceand said switch where'- by a movement of said device fromone limit of its movement first closes said switch and then reduces saidresistance.

39. In combination, a variable resistance, a reversin switch, apower-operated device, mechanic connections from said device to saidresistance and said 'switch'whereby a movement of said device from onelimit of its movement first closes said switch and then reduces saidresistance, and means it'or reversing the direction in which such movement of said device closes sa d reversing switch I I 40.. Incombination, a variable resistance, a reversing switch, a power-operateddevice,

mechanical connections from said device'to said resistance and saidswitch wherebya movement of said device from one lim1t 0:

its movement first closes said switch and r then reduces saldresistance, means for re versing the direction in which such movement ofsaid device closes said reversing switch, and means for preventing suchseversal save when the reversing switch in open position. 41. Incombination, a reversing switch, a power-operated device, and means forme: chanically connecting said device to switch so. that a givenmovement of the former may operate. the latter in either desireddirection. l 42. In combination, a reversingswitcn, :1 power-operateddevice, means for mechanically connecting said device to said switch sothat a given movement of the former my operate the latter in eitherdirection,

means for preventing breaking of said mechanical connection save whenthe reversing switch is inopen pgsitlon. g

43. In combination, a variable resistance, a reversing switch, andunitary power-operated operating means which when moved from one lim1tof its movement, may close said switch in either direction and reducessuch resistance.

44'. In combination, a reversing switch, a

power-operated device, and means arranged -when moved on either side ora neutral position to control in the same-manner the suppl 'ofenrgy tosaid device and when" move on op osite sides of the neutral position toma e mechanical conne :tions between said device and said switch so thatthe same movementof said device causes opposite movements of the switch.

45. In combination, a reversing switch, power-operated operating meanstherefor. and means whereby the same movement of said operating meansmay be made to roduce at will opposite movements of sai reversingswitch. 4

Milwaukee, Wis, April 12, 1910.

In testimony whereof I aflix my signature,

in the presence of two'witnesses.

) HERBERT W. CHENEY l Witnesses:

Gno. B. SGHLEY,

OHAS. L. BYRON.

